Sleep-Wake Disorder Drug Hetlioz Gets Nod in Europe

Pauline Anderson

April 24, 2015

The European Medicines Agency (EMA) has recommended marketing authorization for tasimelteon (Hetlioz), a melatonin-receptor agonist, for the treatment of adults with a chronic circadian rhythm condition called non–24-hour sleep-wake disorder (non-24).

Tasimelteon would represent the first European Union (EU) treatment for non-24, the agency said in a press release.

The drug was approved early last year by the US Food and Drug Administration (FDA), also the first FDA approval of a treatment for the disorder.

Non-24 is a rare condition that occurs almost exclusively in blind people. Because they don't perceive light, these patients fall asleep and wake up at different times compared with the general population, often in a pattern that is closer to a 25-hour clock.

As a result, they have problems adjusting to the standard timetable of everyday life, often being awake or asleep at unusual times. Many experience excessive daytime sleepiness, which affects their quality of life and ability to follow a normal daily schedule.

Melatonin, produced by the pineal gland during hours of darkness, plays a key role in coordinating the body's sleep cycle by acting on receptors in the brain.

The effectiveness of tasimelteon was demonstrated in two clinical trials. These studies showed that treatment resulted in significant improvement compared with placebo, both in increasing night-time sleep and decreasing daytime sleep duration.

The most common adverse effects include headache, drowsiness, and nightmares or unusual dreams.

Orphan Drug

In 2011, tasimelteon received an orphan designation in Europe. This designation and the associated incentives, such as scientific advice, are among the most important instruments to encourage the development of medicines for patients with rare diseases, said the press release.

The opinion adopted by the Committee for Medicinal Products for Human Use (CHMP) at its meeting this month is an intermediary step on Hetlioz's path to patient access. This opinion will now be sent to the European Commission for the adoption of a decision on EU-wide marketing authorization.

Once marketing authorization is granted, each Member State will decide on price and reimbursement, considering the potential role/use of this medicine in the context of the national health system of that country.

The marketing authorization applicant for Hetlioz is Vanda Pharmaceuticals Limited, United Kingdom. In the United States, the drug is manufactured by Vanda Pharmaceuticals Inc, Washington, DC.

According to the FDA, up to 100,000 Americans have non-24 and can't perceive enough light to establish a normal night sleep schedule. If prescribed tasimelteon, they should take this drug at the same time every night before bedtime and limit activities after taking it.


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